The present invention relates to a radial internal combustion engine with spherical pistons having a unique cam configuration to establish relative constant velocity reciprocation of the pistons.
In my patent application entitled "Four Stroke Continuous Cycle Radial Piston Engine", Ser. No. 094,708 filed on Jul. 22, 1993, which is a continuation-in-part of Ser. No. 889,439 filed on May 28, 1992, now U.S. Pat. No. 5,257,599, I describe a radial internal combustion engine with spherical pistons which ride on a circular cam surface whose center of rotation is offset from the center of rotation of the cylinders. The spherical pistons, in addition to rolling around on the cam surface in a circular motion, also have reciprocating motion relative to the cylinders. The velocity of each of the pistons along its circular path as well as the relative reciprocation varies significantly over the cycle of rotation.
The non-uniform velocity of the pistons along their circular paths results in some sliding and slipping of the spherical pistons instead of pure rolling motion along the cam surface during velocity changes. This causes extra wear due to friction and increased noise. In addition, the non-uniform motion can be shown to cause the pistons to "bunch up" in one portion of each cycle resulting in an unbalancing effect and increased vibration in the engine.